A breathing gas supply unit for mounting in an airplane has become known from DE 41 40 266 C1. Such breathing gas supply units are arranged in ceiling structures in the passenger compartment of airplanes and are used to supply the passengers with the oxygen needed for breathing in the case of need. The container of the breathing gas supply unit comprises a container lower part, in which a plurality of oxygen masks and an oxygen generator are arranged, and a container door, which is pivotable around an axis and is used to close the container.
Rail sections, which extend in parallel to the pivot axis of the container door and with which the complete breathing gas supply unit can be fastened in a bracket in the ceiling structure of the airplane, are arranged at the front and rear edges of the lower part of the container. The rail sections are used to simplify the mounting of the breathing gas supply unit in the ceiling structure, on the one hand, and, on the other hand, they also facilitate the removal because the complete breathing gas supply unit can be removed from the ceiling structure without tools. Other components in the ceiling structure, hereinafter called panel, are also fastened with rail sections and are arranged directly next to the breathing gas supply unit. Based on the manufacturing and mounting tolerances, a certain height offset between the breathing gas supply unit, and here especially the container door, and adjacent panels is always possible. Since the container door directly adjoins adjacent panels, any dimensional difference impairs the overall optical impression made by the interior space of the airplane. Possible dimensional differences must be eliminated by adjusting the lower part of the container in relation to the container door, which causes high costs.